Results: Yields of templated beads look fabulous. Recoveries of templated beads are a bit on the high side (desired recoveries are between 5-15%, with 20% being the “cutoff” that Rhonda’s lab uses for runs. The Lean and Sisco samples cross this cutoff value. Will consult with Steven to see what how he wants to proceed (i.e. new ePCRs?). Beads stored @ 4C until ready for running on the SOLiD.

ePCR was performed for the above three mentioned SOLiD libraries using 1.5pM (180 pg/uL) of cDNA, according to the ABI “full scale” ePCR protocol. ePCRs were stored @ 4C until ready for the emulsion breaking step.

Amounts of cDNA used to make dilutions (in 1x Low TE Buffer) of 180pg/uL:

Amplified cDNA was cleaned up using the Invitrogen PureLink Micro Kit, but was done so according to Ambion’s Whole Transcriptome Analysis Kit protocol and then spec’d.

Results:

0.5uL was removed from each sample and mixed with 0.5uL to run on DNA 1000 chips on the Bioanalyzer 2100. The slideshow below shows the electropherograms from each sample. Each sample (to be considered worthy of moving to the next stage) should have <20% of the sample in the 25-150bp range. All 8 samples exhibit this and their peaks look very good. Will proceed to ePCR/templated bead prep next week.

cDNA was gel purified according to Ambion’s Whole Transcriptome Analysis Kit. The appropriate regions (100 – 200bp) were excised and cut in to 4, 1x5mm pieces. The two “internal” pieces were transferred to individual PCR tubes. The “outer” pieces were transferred together to a 1.5mL snap cap tube and stored @ -20C.

Three images are below. The first two are the gels before excising the 100 – 200bp region of the gel. The third is the image of the SECOND gel after the specified region was excised. An image was not taken of Gel 1 after excision (whoops!).

Gel 1

Gel 2

NOTE: The WB sample in the gell above is actually a yellow perch sample, NOT an abalone sample!

Gel 2 AFTER EXCISION

NOTE: The WB sample in the gell above is actually a yellow perch sample, NOT an abalone sample!

In-gel PCR was performed on the individual “internal” gel pieces that were excised, as described below from earlier today. PCR rxns/cycling were performed according to Ambion’s Whole Transcriptome Analysis Kit. PCR ran O/N. PCR master mix set up is here (bottom half of sheet).

Samples were speedvac’d to dryness and resuspended in 3uL of nuclease-free H2O. Samples were then reversed transcribed according to Ambion’s Whole Transcriptome Analysis Kit. RT master mix set up is here (top portion of sheet).

Fragmented mRNA according to Ambion’s Whole Transcriptome Sequencing Kit. Cleaned up sample using Ribominus Concentration Module (Invitrogen) according to Ambion’s WTS Analysis Kit. Samples were eluted w/20uL of H2O and stored @ -80C. Will Bioanalyze and speedvac at a later date.

Total and mRNA aliquots (~5ng/uL) were run on the Agilent Bioanalyzer Pico RNA chips.

Results:

The gel below shows the comparison/results of total RNA and subsequent mRNA isolations. The gel indicates the following:

The HPWS09 total RNA (Herring) is totally degraded, but shows the expected profile in the mRNA prep. It would be extremely interesting to see if the degradation has any effect on sequencing, as the mRNA will get fragmented any way in the next step of library construction.

mRNA isolations worked for all samples. Although one might be inclined to say that mRNA isolation did NOT work for the WB sample, one has to take in to consideration that the gel software adjusts the gel contrast to enhance low signals. That’s why all the mRNA samples exhibit a dark background. mRNA generates a broad, relatively weak signal when compared to a total RNA sample. So, the software attempts to boost the low signal for display purposes. Thus, if we were to decrease this signal boosting (or contrast) for the WB mRNA so that the background color matched the WB total RNA background color (white), the rRNA bands visible in the WB mRNA sample would fade to a point where they would not be visible. See the electropherogram overlay (below the gel) for a more visual comparison of this concept.

Electropherogram Overlays of WB total RNA and WB rRNA

The WB total RNA is the red graph which shows extremely high levels of rRNA (as expected). After subsequent mRNA isolation (the blue graph), the rRNA is virtually gone and no longer comprises a significant portion of the sample.

mRNA was pelleted and washed according to Ambion’s MicroPolyA Purist Kit. Pellets were resuspended in 8uL nuclease-free H2O and spec’d. 0.5uL was taken from each sample, transferred to a fresh tube, diluted to ~5ng/uL and stored @ -80C for eventual Bioanalyzer analysis. mRNA samples were stored @ -80C until we receive the Ribominus Concentration Module Kit from Invitrogen (turns out we didn’t have any!) for cleaning up the RNA after fragmentation.

Results:

Overall, this mRNA doesn’t look that great. However, I did notice that all samples had (to varying degrees) particulate matter that wouldn’t dissolve. Prior to spec’ing, the particulate matter was pelleted so as to not interfere. All samples will continue to be prepped for SOLiD analysis despite poor 260/280 ratios and low yields.